Mold with integral screen and method for making mold and apparatus and method for using the mold

ABSTRACT

A mold with integral screen comprising a body of material having a surface, the body has a grid-like pattern of vacuum holes extending through the body of material and opening through said surface and permitting a vacuum to be supplied to said surface, a screen overlying said surface, said screen and said body being formed of the same material as the body and being integral.

[0001] This invention relates to a mold with integral screen and methodfor making the same and particularly to a mold with integral latticeworkparticularly useful as a tool for making articles from a fiber or pulpslurry to provide molded pulp parts and an apparatus and method forusing the mold to produce molded pulp parts.

[0002] Molds have heretofore been provided for producing molded fiberproducts. Typically such molds have been called wet molds because theyare dipped into a wet vat of a fiber or pulp slurry. Such a slurrytypically is made from reclaimed paper such as newspapers, corrugatedmaterial and the like. Such molds often have been formed of aluminum toprovide the desired surface or face through which vacuum holes extend.In such molds, the surface of the mold is typically covered with ascreen such as of stainless steel which is sized to fit and cut and spotwelded to conform precisely to the surface of the mold to provide themold surface. Such screens are used to prevent the fibers from cloggingthe vacuum holes. Such a screen makes it possible to disperse the vacuumevenly over the entire surface of the mold and to prevent the fibersfrom clogging the vacuum holes. Such molds typically are quite expensivebecause of the time required to make the mold. In addition with suchmolds, the screens can readily tear during production requiring that thescreens be repaired or replaced. There is therefore a need for a new andimproved mold or die which overcomes the above-identified disadvantages.

[0003] In general, it is an object of the present invention to provide amold or die that has a body with an integral screen or latticework andmethod for making the same which greatly reduces the time and expenserequired for making a mold suitable for molding products from fiber orpaper pulp.

[0004] Another object of the invention is to provide a mold or die andmethod of the above character in which the die can be provided which hasa body that is integral with the latticework and in which the body andthe latticework can be fabricated at the same time by the use of thesame material.

[0005] Another object of the invention is to provide a mold or die andmethod of the above character which can readily accommodate complexshapes.

[0006] Another object of the invention is to provide a mold or die andmethod of the above character which provides a molded product havingunique surface texture provided by the latticework of the mold or die.

[0007] Another object of the invention is to provide a mold or die andmethod of the above character in which the architecture of the moldincorporates a body of the material which does not adversely affectoperation of the latticework or screen.

[0008] Another object of the invention is to provide a mold or die andmethod of the above character in which the mold or die can be createdwith great precision.

[0009] Another object of the invention is to provide a die and integralscreen of the above character which can be produced rapidly with greatprecision and at a greatly reduced cost.

[0010] Another object of the invention is to provide an apparatus andmethod for using the mold or die of the above character in which themolded pulp product can be dried by the use of heat on the mold beforethe product is transferred.

[0011] Another object of the invention is to provide an apparatus andmethod using the mold or die of the above character in which a vacuumcan be maintained on the molded product while heat is being applied tothe molded product.

[0012] Another object of the invention is to provide an apparatus andmethod of the above character in which the mold or die when in use willpermit liquid to pass through the mold or while retaining the fibers ofthe molded pulp on the surface of the mold or die.

[0013] Another object of the invention is to provide an apparatus andmethod of the above character which is used for producing a precisionmolded product.

[0014] Additional objects and features of the invention will appear fromthe following description in which the preferred embodiments are setforth in detail in conjunction with the accompanying drawings.

[0015]FIG. 1 is an isometric view of a mold or die with integrallatticework incorporating the present invention.

[0016]FIG. 2 is greatly enlarged of the view of a portion of thelatticework shown in FIG. 1 encircled by the line 2-2 of FIG. 1.

[0017]FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 1.

[0018]FIG. 4 is a schematic illustration of an apparatus incorporatingthe present invention utilizing the molds of the present invention formaking molded products.

[0019]FIG. 5 is an isometric top view of another embodiment of a moldincorporating the present invention.

[0020]FIG. 6 is cross-sectional view taken along the line 6-6 of FIG. 5.

[0021]FIG. 7 is another cross-sectional view similar to FIG. 6 but only0.004″ in thickness.

[0022]FIG. 8 is a bottom plan view of the mold shown in FIG. 5.

[0023] In general, the die with integral latticework of the presentinvention is for use as a mold in making molded pulp products from afiber slurry that comprises a body formed of a material. A latticeworkis carried by the body to provide a mold surface for making the moldedpulp product. The latticework is provided with a plurality of meanstherein spaced substantially uniformly across the mold surface which aresized to permit a vacuum to be pulled therethrough but to prevent fibersfrom the pulp from being pulled therethrough so that the fibers from theslurry will build up on the latticework. Means is provided by the bodyfor supporting the latticework on the body to provide a plurality ofpassages in communication with the openings in the latticework whereby asubstantially uniformly distributed vacuum is supplied by thelatticework when a vacuum is supplied to the die. The latticework andthe means supporting the latticework are formed of the same material.

[0024] More in particular as shown in FIGS. 1, 2 and 3 of the drawings,the die or mold or tool 11 with integral screen or latticework consistsof a body 12 formed of a suitable material which can be utilized inrapid prototyping and manufacturing technology and particularly thosematerials suitable for use with stereolithography. As is well known tothose skilled in the art, selective laser sintering is utilized tocreate solid three-dimensional objects, layer by layer from plastic,metal or ceramic powders that are “sintered” or fused using laserenergy. The body 12 as shown can be in the form of a parallelepipedhaving spaced-apart parallel side surfaces 13 and spaced apart parallelend surfaces 14 extending perpendicular to the side surfaces 13. Thebody 12 is also provided with a bottom surface 16 (FIG. 3) which extendsat right angles to the surfaces 13 and 14 and a top surface 17 whichextends at right angles to the side and end surfaces 13 and 14 andparallel to the bottom surface 16.

[0025] The top surface 17 of the body or block 12 has formed therein acomplex die or mold surface 21 of a desired configuration as for exampleone which is recessed as shown. The mold surface 21 has complex shapesformed therein as for example curved or concave side walls 22 adjoiningconvex or truncated semi-spherical surfaces 23 which adjoin spaced apartcircular planar surfaces 24 that lie in a common plane. This complexmold surface 21 has been shown in the drawings to depict how a moldsurface which has complex curves therein can be provided in accordancewith the present invention.

[0026] A screen or latticework 31 is provided which will serve as themold surface 21 for making a molded pulp product as hereinafterdescribed. The screen or latticework 31 is provided with a plurality ofspaced-apart openings 32 which are spaced substantially uniformly acrossthe mold surface 21 and generally lie in a plane having the conformationdesired for the mold surface 21. The openings 32 are sized in such amanner so that the fibers from the pulp will not be pulled through theopenings 32 but will build up to form the mold product on the screen orlatticework 31 serving as the mold surface 21. The openings 32 are sizedin such a manner so that a vacuum supplied to the underside of thescreen or latticework 31 into a chamber 33 through a fitting 34connected to a suitable vacuum source 35 will pull the fibers from thefiber slurry into contact with the screen or latticework 31 to form themolded pulp product. The size of the openings can range from 0.24″ to0.32″ and can be of a desired configuration as for example circular,square or rectangular. The preferred size has been found to beapproximately 0.24″×0.24″ when utilized in connection with making moldedproducts from fiber slurries made from recycled newspapers and the like.

[0027] Means is provided as a part of the body 12 in the form of athree-dimensional grid-like support structure 36 that provides aplurality of passages 37 extending through the grid-like structure andunderlying the screen or latticework 31 with each of the passages beingin communication with one or more openings 32 of the screen orlatticework 31. The vacuum hereinbefore described is in communicationwith the passages 37 and in conjunction with the screen or latticework31 supplies a vacuum which is substantially uniformly distributed overthe mold surface 21.

[0028] In connection with the present invention, it has been founddesirable to utilize the same material for forming the body 12, thelatticework 31 and the grid-like support structure 36. In connectionwith the present invention it has been found to be particularlydesirable to utilize polyamides and particularly Nylon because of itsexcellent heat and chemical resistance which are desirable qualities forthe dies and tools made for producing molded pulp products of thepresent invention as hereinafter described. Two materials found to beparticularly suitable are those supplied by DTM Corporation of Austin,Tex., U.S.A. and identified as Duraform™ Polyamide and Duraform GF(glass-filled) supplied by that corporation. In other applications,other materials supplied by that corporation can be utilized such asDuPont Somos® 201 TPE, TruForm™ Polymer, SandForm™ Zr II and Si FoundrySands, Copper Polyamide and RapidSteel® 2.0.

[0029] In utilizing Nylon, the Nylon powder is spread as a thin uniformlayer of a suitable thickness as for example 0.004″ across the buildarea by forming a powder bed with the use of a leveling roller in abuild chamber of suitable apparatus such as supplied by DTM Corporationof Austin, Tex., and identified as the Sinterstation® 2500^(plus). Across-section of the die or mold is selectively imaged by a computerdriven program onto the layer of powder using laser energy which heatsthe powder to a temperature above its softening or melting temperatureand thereby sintering or fusing the particles into a solid mass. Thelaser power is modulated so that only powder which conforms to themold's geometry is fused. Progressive layers of powder are thereafterspread across the build area and rolled and imaged in the same manneruntil the complete mold has been imaged and formed. Thereafter the moldis removed from the build chamber and the loose unfused powder isremoved to provide the finished mold.

[0030] In the specific construction shown in FIGS. 1, 2 and 3, thescreen or latticework 31 is formed by the use of a plurality ofuniformly shaped articles 41 in the form of spheres having at least fourspaced-apart contact points 42 (see FIG. 2). These spheres can be of asuitable size as for example from 0.030″ to 0.090″ and preferably 0.060″to 0.070″. The screen or latticework 31 formed by the articles 41 issupported by the grid-like support structure 36 in which the passages 37extend through the grid-like support structure 36 which is provided witha surface 43 through which the passages 37 extend. The articles 41 makecontact with the surface 43 at points 44 to define subways 46 whichextend across the surface 43 in longitudinal and transverse directionsin accordance with the pattern formed by the articles 41 so that theopenings 32 between the articles 41 are in communication with thesubways 46 and the subways 46 are in communication with the passages 37in the grid-like support structure.

[0031] From the foregoing description it can be seen that the size ofthe openings 32 and the subways 46 can be readily changed by merelychanging the size of the spherical articles 41. For the articles 41instead of using spheres, it should be appreciated that other geometricshapes can be utilized as for example polyhedrons having six or moresurfaces. Thus for example a polyhedron having eight surfaces with fourplanar surfaces at the top forming a four-sided pyramid and foursurfaces at the bottom forming another four-sided pyramid with the twopyramids being joined together to provide an eight-sided polyhedron.Such an eight-sided polyhedron has four corners or points which lie in aplane which can be adjoined to corners of adjacent polyhedrons tothereby in effect provide a latticework which has openings 32 extendingtherethrough which are in communication with subways 46 that are incommunication with the passages 37 of a grid-like support structure.Similarly, it can be seen that the articles can be formed as truncatedpolyhedrons as for example a four-sided pyramid with the bottom side ofthe pyramid facing upwardly to provide a planar surface having openings32 therebetween and having subways 46 therebelow in communication withthe passages 37 of a grid-like support structure 36. All of thesevarious constructions can be readily formed utilizing the technologyhereinbefore described.

[0032] Molds made in accordance with the present invention have been byway of example made of Duraform™ Nylon which is an FDA-approved gradeNylon which can readily accommodate operating temperatures of 300° F. Ithas been found, however, that the exterior surfaces of such molds sincethey are formed of Nylon which is originally in a powder state have inminutiae a rough surface which can inhibit the release of the that hasbeen molded. To enhance the release characteristics of the mold, theexterior surface of the mold is coated with a heat-resistant materialidentified as Xylan™ which can withstand temperatures up to 450° F.Xylan is a fluorocarbon coating. This material is sprayed on in threesuccessive layers, each of 2-3 mil in thickness and each layer beingpost-cured at 300° F. for 30 minutes on each layer. This coating 48 canbe colored. Yellow has been selected as an appropriate color because itmakes the fibers appearing on the mold to be more visible. It has beenfound that this coating 48 provides a very smooth, slippery surfacewhich provides the mold with greatly enhanced release characteristics.

[0033] Another mold or tool incorporating the present invention is shownin FIGS. 5, 6 and 7. As shown therein, the mold 91 is formed of asuitable material such as the Duraform Nylon hereinbefore described byuse of a Sinterstation as hereinbefore described. The mold 91 isprovided with a circular frame 92 which is provided with a radiallyextending flange 93 having bolt holes 94 therein. The mold 91 is in theform of a truncated cone 96 which is provided with an inclined surface97 and a planar circular surface 98 which adjoins the inclined surface97. A truncated cone-shaped recess 101 is provided within the cone 96and has a conformation generally corresponding to the cone 96 but ofsmaller dimensions so that there remains a body 106 which is supportedby the frame 92. The body 106 includes a grid-line support structure 107which is overlaid by a screen or latticework 108 which forms the outersurfaces 96 and 97 of the truncated cone 96.

[0034] The grid-like support structure 107 is a plurality ofspaced-apart parallel struts 111 extending in one direction and aplurality of additional spaced-apart struts 112 forming the grid-linestructure 107. The struts can have a suitable thickness as for example0.042″ with the spaced between the struts in both directions beingapproximately ¼″ to provide holes 116 which are rectangular incross-section and have a suitable dimension as for example ¼″ by ¼″.These holes extend from the space provided by the cone-shaped recess 101which is exposed to a vacuum and which extend to the screen orlatticework 108. It can be seen that by providing the cone-shaped recess101, the holes 116 have a length which is substantially equal so thatthe length of the flow passages for the vacuum to travel to the screenor latticework 108 is substantially the same to thereby provide asubstantially uniform vacuum over the screen or latticework 108.

[0035] The screen or latticework 108 is formed of a single layer ofmaterial which is supported by the grid-like structure 107 which isshown in the top circular surface 98 and which is formed by a pluralityof spaced-apart parallel struts 121 and a plurality of additionalspaced-apart parallel struts 122 extending at right angles to the struts121 to provide holes 123 between the same. These struts 121 and 122 canhave a suitable thickness as for example 0.020″ and having rectangularholes 123 therebetween of a suitable size as for example 0.02″ by0.020″. This same type of hole pattern is continued down over theinclined surface 97. Because of this inclined surface, the holes 126therein are in the form of inclined parallelograms and are of such alarger size as for example 0.020″ by 0.04″. The struts are of a suitablethickness as for example 0.040″.

[0036] A logo or other identification 131 can be provided on the topsurface 98 which mold would be incorporated into the part made from themold. If desired, this logo 131 can be imperforate. The struts 127 and128 define the holes 126 are elliptical and form ellipses on theinclined surface 97.

[0037] A mating mold (not shown) can be prepared in a similar manner.The molds thus prepared can be coated with the coating of the typehereinbefore described to enhance the release characteristics for themold. The mold 91 and its mating mold can be utilized in the apparatusshown in FIG. 4 and can be utilized in the same manner to produce moldedparts therefrom. The molded parts produced from such molds have a verypleasing appearance which corresponds to the appearance of the exteriorsurface of the mold, thus providing a molded part which is precisionmolded and which also has a very pleasing, relatively smooth surface.

[0038] From the molds shown in FIGS. 6 through 8 it can be seen thatvery sophisticated molds can be prepared in accordance with the presentinvention within relatively short periods of time and at relatively lowcost. Thus such molds can be utilized for short run molded products whenthat becomes necessary.

[0039] Molded pulp products of the desired configuration can be made inmolded pulp product producing apparatus 51 as shown in FIG. 4. In suchapparatus, a tool set 52 is required formed of a female mold or tool 53and a mating male mold or tool 54. Such molds or tools can be readilyprepared in accordance with the present invention. For example thedesired part can be drawn utilizing a CAD data format in a conventionalcomputer and transferring it by disk to an STL format to theSinterstation® 2500^(plus) hereinbefore described. The surfaces to begenerated for the female and male molds are obtained by selecting theappropriate surfaces of the part and then inputting the desiredthickness for the molded part to provide the necessary space between thefemale and male molds. Both the female and male molds are then formed inthe Sinterstation® 2500^(plus) by forming each of the molds with thescreen or latticework 31 having the openings 32 therein and defining thesurfaces of each mold.

[0040] The molds 53 and 54, after they have been prepared, are placed inthe apparatus 52 by mounting the female mold 53 on a manifold 61 mountedon a plunger 62. The plunger 62 reciprocates vertically to bring themanifold 61 with its female mold 53 down into a fiber slurry 63 disposedin a holding tank 64 and out of the slurry 63. The manifold 61 isconnected by piping 66 to a vacuum source 67. It is also connected bypiping 68 to a source of compressed air 69.

[0041] The male mold or tool 54 is mounted on a transfer manifold 71which is carried by a plunger 72 that also reciprocates vertically andis movable upwardly and downwardly with respect to the manifold 61. Thistransfer manifold 71 is connected by piping 76 to the vacuum source 67.It is also connected by piping 77 to a source of hot air 78.

[0042] The vacuum source 67 typically should be capable of producing avacuum ranging from 26-29″ of Hg with a preferable vacuum beingapproximately 28.5″ of Hg. The hot air source 78 produces hot air underpositive pressure at a temperature ranging from 250-310° F. with apreferred temperature of approximately 290° F. and a pressure rangingfrom 15 to 100 psi with preferably a pressure of approximately 50 psi.

[0043] The tool set 52 shown in FIG. 4 can be utilized for producing amolded pulp product which is capable of providing packaging for afragile product such as champagne flutes. Such tool by way of examplecan be 9″ in length, 5″ in width and 6″ in height.

[0044] In producing the molded pulp product, the manifold 61 isrepeatedly lowered into the slurry 66. As soon as the manifold 61 andthe female tool or mold 53 are completely immersed in the fiber slurry,a vacuum is supplied from the vacuum source 67 which vacuum is uniformlydistributed throughout the tool 53 because of the porosity of the toolprovided by the passages 32, 37 and 46 hereinbefore described. Theuniformly distributed vacuum over the tool causes fibers to be withdrawnfrom the fiber slurry 66 and to be deposited substantially uniformlyover the entire surface of the tool or mold 53. A sufficient thicknessof fibers is collected onto the female mold 53 which can occur on asingle immersion but if necessary after repeated immersions, with thevacuum being applied continuously. When the desired thickness of fibershas been achieved, the mold 53 is raised out of the slurry 63. At thesame time, transfer manifold 71 is lowered so that male tool 54 carriedthereby mates with female tool 53 to create a seal between the two toolswhile at the same time maintaining a void of the desired smalldimensions between the female and male tools 53 and 54. The male tool 54heated by the hot air from the hot air source 78 causes drying of themolded material carried in the female tool to dry the same while thevacuum is still being applied for removing the moisture which is beingdriven off from the molded material. The drying temperatures utilized of300° F. can be readily accommodated by the Nylon forming the tools 53and 54.

[0045] After the drying operation has been completed which typically cantake place in 2 to 10 seconds and usually about 5 seconds, the vacuumfrom the vacuum source 67 is terminated. A burst of compressed air isalso supplied at approximately the same time from the source 69 to themanifold 61 to aid in lift off of the molded part from the female tool53. Also at the same time separation of the molds 53 and 54 occurstypically by raising of the transfer manifold 71. A vacuum is suppliedto the transfer mold 71 to aid in separation of the molded part from thefemale mold 53 and lifting of the molded part by the male tool 54. Thisseparation of the molded part is greatly facilitated by the coating 48applied to the exterior surface of the molds or tools. The hot air underpressure from the hot air source 78 is terminated immediately prior tolift off of the molded part. The transfer manifold 71 with the tool andthe molded part carried thereby after it has been raised a sufficientdistance can be shifted to overlie a conveyor belt (not shown) andthereafter, the vacuum can be released to permit the dried molded partto drop off of the transfer mold.

[0046] As explained previously, if the thickness of the molded pulpformed on the female tool 53 during the initial immersion into the fiberslurry does not produce a molded product of sufficient thickness, evenbefore the drying step is undertaken, the manifold can be again loweredinto the fiber slurry 66 to cause additional fibers to be picked up onthe slurry by the use of the vacuum from the vacuum source 67. As soonas the desired thickness of the pulp material has been provided on thefemale tool 53, the drying step hereinbefore described can beaccomplished.

[0047] From the foregoing it can be seen that there has been provided anew and improved die or mold with integral screen or latticework and amethod for making the same which greatly facilitates the production ofmolds, particularly those requiring the use of screens used for formingmolded pulp articles. Such dies can be economically and rapidlymanufactured to make it possible to rapidly and readily producedifferent molded products having various conformations and shapes. Theuse of the spheres for forming the latticework is very desirable becausethey do not require orientation. However, as pointed out above, otheruniformly shaped articles can be utilized to achieve similar resultswith the only difference being that they must be oriented with respectto the mold surface. Such orientation can be readily accomplished with aCAD (computer aided design) program generating the desired pattern.There also has been provided an apparatus and method for using the moldsto produce molded products economically.

What is claimed:
 1. A mold with integral screen comprising a body formedof a material having a surface, said body having a grid-like pattern ofvacuum holes extending through the material and opening through saidsurface and permitting a vacuum to be supplied to said surface and ascreen overlying said surface, said screen and said body being formed ofthe same material as the body and being integral.
 2. A mold as in claim1 wherein said material forming said body and said screen is a sinteredmaterial.
 3. A mold as in claim 2 wherein said grid-like pattern isformed by a plurality of struts extending at angles with respect to eachother and providing the vacuum holes extending to the screen.
 4. A moldas in claim 3 wherein the screen is formed of a plurality ofspaced-apart parallel struts extending at angles with respect to eachother and defining holes therein in communication with the vacuum holesof the grid-like pattern of the body.
 5. A mold as in claim 1 whereinsaid screen has a complex surface.
 6. A mold as in claim 1 wherein saidscreen has an exterior surface and further including a release coatingformed on the exterior surface.
 7. A mold as in claim 6 wherein saidrelease coating is formed of Xylan.
 8. A mold as in claim 1 wherein saidvacuum holes in said grid-like pattern have substantially the samelength so as to provide a substantially uniform vacuum to the screenwhen a vacuum is applied to the mold.
 9. A mold as in claim 1 whereinsaid mold is formed of a material which is capable of withstandingtemperatures in excess of 300° F.
 10. A mold as in claim 7 wherein saidrelease coating is a heat resistant coating capable of withstandingtemperatures of 430° F.
 11. Apparatus for producing molded pulp productsby the use of first and second mating molds being formed of a porousmaterial and capable of withstanding temperatures in excess of 300° F.,a first manifold for carrying the first mold and means for moving thefirst manifold and the first mold carried thereby into a fiber slurryfor forming the molded part of molded pulp, means for applying a vacuumto the first manifold to cause a vacuum to be applied to the first moldwhen the first mold is immersed in the fiber slurry, a second transfermanifold mounting the second mold, means supplying heat to the secondtransfer manifold and the second mold, means for moving the secondtransfer manifold and the first manifold to bring the first and secondmolds into engagement with each other, means for maintaining a vacuum onthe second transfer manifold and the first manifold, means for applyingheat to the second transfer manifold to cause drying of the molded pulpcarried by the first mold to provide the molded part, means for causingrelative movement between the second transfer manifold and the firstmanifold and means for at substantially the same time supplyingcompressed air to the first manifold to cause the molded part to beseparated from the first mold and to move with the second transfer mold,and means for thereafter releasing the vacuum on the second transfermanifold to permit separation of the molded part carried by the secondtransfer mold.
 12. Apparatus as in claim 11 wherein said means formoving the first manifold is capable of immersing the first moldrepeatedly into the fiber slurry until a sufficient thickness of fibershas been formed on the first mold for the molded part.
 13. A method forforming a mold with an integral screen, generating by computer alatticework providing a mold surface having a plurality of openingstherein and grid-like support means underlying and supporting thelatticework and providing a plurality of passages extending upwardly toand in communication with the openings in the screen, converting thecomputer program into a stereolithographic program for manufacturing themold, latticework and the grid-like support and means utilizing thestereolithographic program to form the latticework and the grid-likesupport means from the same material.
 14. A method as in claim 13further including the step of providing a powder of a plastic materialand sintering the powdered material utilizing the stereolithographicprogram.
 15. A method for producing molded parts from a fiber slurry bythe use of first and second mating porous molds, moving the first moldinto a fiber slurry and supplying a vacuum to the first mold to causefibers from the fiber slurry to form onto the first mold to a desiredthickness, heating the second mold, mating the first and second moldsand supplying a vacuum to the first and second molds during mating ofthe first and second molds and while heating is supplied to the secondmold to cause solidification and drying of the fibers carried by thefirst mold until the fibers on the first mold are at leastself-supporting to provide a molded part, ejecting the molded partformed by the fibers so that the molded part will travel with the secondmold as the second mold is moved, moving the second mold and releasingthe vacuum on the second mold to permit the molded part to be separatedfrom the second mold.
 16. A method as in claim 15 wherein compressed airis utilized for ejecting the molded part from the first mold.